Abstract

We have studied the effect of double-functionalization on goldelectrodes for improving nanopore-based DNAsequencing. The functionalizing molecular probes are, respectively, capable of temporarily forminghydrogen bonds with both the nucleobase part and the phosphate group of the target DNA, thus potentially minimizing the structural fluctuations of a single-stranded DNA molecule passing between the goldelectrodes. The results of our first-principles study indicate that the proposed setup yields current signals that differ by at least 1 order of magnitude for the four different nucleic acid bases, thus offering the possibility to electrically distinguish them.

Received 16 September 2011Accepted 07 November 2011Published online 09 January 2012

Acknowledgments:

Financial support is gratefully acknowledged from the Royal Thai Government, the Carl Tryggers Foundation, the Uppsala University UniMolecular Electronics Center (U3MEC), Wenner-Gren Foundations, and the Swedish Research Council (VR, Grant No. 621-2009-3628). The Swedish National Infrastructure for Computing (SNIC) and the Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX) provided computing time for this project.